MARKET URBANISM PRESENTS:

by Sandy Ikeda

Ch. 1 What is a City?: Complexity and radical ignorance

May 7, 2018 By Sandy Ikeda

First of all, Jacobs observed that the artist abstracts from life, with all its “inclusiveness” and “literally endless intricacy.” Many architects, especially those with great ambition, seem to treat urban environments as merely a canvas for their works of genius, which if not already blank needs to be wiped clean before getting to work. The good ones at least try to take into account how their constructions fit or don’t fit into the existing built environment and how real people might actually use them. But whether you’re an architect or an economist, predicting how people will respond to a change is a pretty iffy thing. From my perspective that iffiness comes from two factors: complexity and radical ignorance.

Complexity in this context means that the interactions among people are so numerous or varied or changeable that the costs of being aware of all of them is too high for anyone to calculate. Hayek defines the degree of complexity in terms of the “minimum number of elements of which an instance of the pattern consists in order to exhibit all the characteristic attributes of the class of patterns in question…” (Hayek 1964). In a world with only a few variables, such as those described in a high-school algebra problem, it is possible to have all the knowledge you need to get the correct answer. In the real world, however, the number of relevant variables is too large, that is the number of ever-changing interactions among people in society is so large, and our cognitive powers are too limited to do that. Compared to the vast complexity of the social order, predicting this week’s weather is a pretty simple matter.

Radical ignorance means being unaware of information that would be relevant to making a decision, not because the cost is too high, but because we are unaware that the relevant information even exists. For example, you might be very hungry but walk blithely by Restaurant X, which serves food that would satisfy your hunger. A simple solution escapes your notice because of your lack of alertness. So whether the problem is complex or relatively simple, not knowing that you do not know means you cannot solve the problem because in some sense you are unaware that the problem even exists.

Acting in the presence of complexity and radical ignorance means that it is impossible to trace all the consequences of your action because (1) you are not even aware of at least some of the consequences and (2) the ramifications of your action are too numerous or subtle to follow given your limited mental capabilities even if you were aware of them. So as a rule the bigger the scale of the changes you wish to make in the real world, or the more detailed the design you wish to impose on a given scale of activity, the harder it will be to predict what is going to happen.

One of the lessons economists learned from the 20th century debate over collectivist central planning – the so-called “socialist calculation debate” – is that the “optimal” level of central planning is lower than most of us think. The local knowledge that makes things work is beyond the grasp of the central planner and accounting for incentives is problematic. And the more someone tries to design a social order, the more people will strive to adjust to her interventions in unforeseen ways, thwarting her intentions. In the context of urban design, that means that substituting the genius of the planner for the collective genius of ordinary people, diminishes the intricacy, complexity, and yes the deep beauty of the resulting social order, and generates negative unintended consequences.

The larger and more elaborate a design is in relation to the social space it’s trying to fit into, the narrower will be the scope of unplanned activities that it can permit. That’s because a structure, of any scale and degree of design, necessarily constrains to some extent how people will use it and the space around it. Building a mid-size townhouse within a commercial block, changes the character of the rest of that block and perhaps also the surrounding neighborhood. The bigger the structure, the bigger the change will be.

In addition, constructing something that takes up an entire city block, like the Empire State Building, not only limits what people can do in and around that space but it also challenges the designer to try to account for the way people will want to use it. Scaling up to something like Lincoln Center or Hudson Yards exponentially increases the difficulty of predicting people’s behavior in and around that space and of constraining how they actually will use it. If she wants to preserve the potential for unplanned liveliness, the designer will need to leave substantial room for adjustment over time, otherwise the level of social complexity will be limited by her imagination at that point in time.

A city can handle endless waves of complex, on-going problems if the rules that govern interaction, and the spaces within which people interact, allow many minds to discover those problems and to work on them over time. Good urban design therefore needs to take seriously into account a city’s “invisible infrastructure” – i.e. the patterns of contact, use, and ever-changing social networks that promote order and social cooperation – that enable individuals to harness their local knowledge (and human capita?). The built environment should complement emergent order, not try to replace it with deliberate design.

It’s a mistake then to approach building structures as different in scale as the Empire State Building, Lincoln Center, or Hudson Yards as one of mere degree. With respect to their impact on the invisible social infrastructure, they are fundamentally different in kind. Increasing the scale of design/construction cuts ever more deeply into the living flesh of a city. The challenge for the designer/builder of public space then is to enable rather than replace the spontaneous, low-level planning of ordinary people, and to preserve – largely by keeping away from – the “action spaces” where informal contact and networking, trial-and-error, diversity, and discovery usually happens. Too often, scaling up progressively drains the life and intelligence from of a city.

[In this space I’ll be posting quotes, ideas, and excerpts relating to a book I’m writing (thus far untitled), which I might describe as “What I have learned from the economic and social theory of Jane Jacobs.” My hope is to get thoughtful, informed feedback that will be useful in shaping the book.]